Wide-Area Networks - CCIE Routing and Switching Exam Certification Guide - page 209

Frame Relay Compression
With Cisco routers, you can configure payload compression on point-to-point or multipoint
interfaces. Either the Stacker method or FRF.9 using the Stacker method can be configured. The
Stacker method uses an encoded dictionary to replace a stream of characters with codes. The
symbols represented by the codes are stored in memory in a dictionary style list. The Stacker
method is not discussed in this topic; however, the following commands configure the router to
use the Stacker method on frame-relay subinterfaces.

For point-to-point subinterfaces use the following command:

frame-relay payload-compress packet-by-packet
For multipoint subinterfaces, the command is as follows:
frame-relay map protocol protocol-address dlci payload-compress packet-by-packet

FRF.9 Compression
Implementation FRF.9 of the Frame Relay Forum provides standards-based compression on
Frame Relay, therefore providing multivendor interoperability. FRF.9 uses higher compression
ratios, which allows more data to be compressed for faster transmission.

To enable FRF.9 compression on a point-to-point subinterface, use the following command:

frame-relay payload-compress frf9 stac
For multipoint subinterfaces, the command is as follows:
frame-relay map protocol protocol-address dlci payload-compress frf9 stac

Frame Relay map Command
Before Inverse ARP was available (prior to 11.2), the most common method to configure Frame
Relay was by using map statements. Looking at Figure 5-9, the serial interface configuration
for Router A is displayed in Example 5-3, and the configuration for Router B is displayed in
Example 5-4.

Router A Frame Relay Map Configuration Example

Example 5-3

interface serial 0
ip address 172.18.1.5 255.255.255.252
encapsulation frame-relay
frame-relay map ip 172.18.1.6 150